AutoIpNetStack - Net stack with AutoIP enabled

Users » darran » Code » AutoIpNetStack

Darran Shepherd / Mbed 2 deprecated AutoIpNetStack

Net stack with AutoIP enabled

lwip/core/mem.c@0:ac21159e27f4, 2010-07-02 (annotated)

Committer:: darran
Date:: Fri Jul 02 17:21:58 2010 +0000
Revision:: 0:ac21159e27f4

Who changed what in which revision?

User	Revision	Line number	New contents of line
darran	0:ac21159e27f4	1	/**
darran	0:ac21159e27f4	2	* @file
darran	0:ac21159e27f4	3	* Dynamic memory manager
darran	0:ac21159e27f4	4	*
darran	0:ac21159e27f4	5	* This is a lightweight replacement for the standard C library malloc().
darran	0:ac21159e27f4	6	*
darran	0:ac21159e27f4	7	* If you want to use the standard C library malloc() instead, define
darran	0:ac21159e27f4	8	* MEM_LIBC_MALLOC to 1 in your lwipopts.h
darran	0:ac21159e27f4	9	*
darran	0:ac21159e27f4	10	* To let mem_malloc() use pools (prevents fragmentation and is much faster than
darran	0:ac21159e27f4	11	* a heap but might waste some memory), define MEM_USE_POOLS to 1, define
darran	0:ac21159e27f4	12	* MEM_USE_CUSTOM_POOLS to 1 and create a file "lwippools.h" that includes a list
darran	0:ac21159e27f4	13	* of pools like this (more pools can be added between _START and _END):
darran	0:ac21159e27f4	14	*
darran	0:ac21159e27f4	15	* Define three pools with sizes 256, 512, and 1512 bytes
darran	0:ac21159e27f4	16	* LWIP_MALLOC_MEMPOOL_START
darran	0:ac21159e27f4	17	* LWIP_MALLOC_MEMPOOL(20, 256)
darran	0:ac21159e27f4	18	* LWIP_MALLOC_MEMPOOL(10, 512)
darran	0:ac21159e27f4	19	* LWIP_MALLOC_MEMPOOL(5, 1512)
darran	0:ac21159e27f4	20	* LWIP_MALLOC_MEMPOOL_END
darran	0:ac21159e27f4	21	*/
darran	0:ac21159e27f4	22
darran	0:ac21159e27f4	23	/*
darran	0:ac21159e27f4	24	* Copyright (c) 2001-2004 Swedish Institute of Computer Science.
darran	0:ac21159e27f4	25	* All rights reserved.
darran	0:ac21159e27f4	26	*
darran	0:ac21159e27f4	27	* Redistribution and use in source and binary forms, with or without modification,
darran	0:ac21159e27f4	28	* are permitted provided that the following conditions are met:
darran	0:ac21159e27f4	29	*
darran	0:ac21159e27f4	30	* 1. Redistributions of source code must retain the above copyright notice,
darran	0:ac21159e27f4	31	* this list of conditions and the following disclaimer.
darran	0:ac21159e27f4	32	* 2. Redistributions in binary form must reproduce the above copyright notice,
darran	0:ac21159e27f4	33	* this list of conditions and the following disclaimer in the documentation
darran	0:ac21159e27f4	34	* and/or other materials provided with the distribution.
darran	0:ac21159e27f4	35	* 3. The name of the author may not be used to endorse or promote products
darran	0:ac21159e27f4	36	* derived from this software without specific prior written permission.
darran	0:ac21159e27f4	37	*
darran	0:ac21159e27f4	38	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
darran	0:ac21159e27f4	39	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
darran	0:ac21159e27f4	40	* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
darran	0:ac21159e27f4	41	* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
darran	0:ac21159e27f4	42	* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
darran	0:ac21159e27f4	43	* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
darran	0:ac21159e27f4	44	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
darran	0:ac21159e27f4	45	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
darran	0:ac21159e27f4	46	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
darran	0:ac21159e27f4	47	* OF SUCH DAMAGE.
darran	0:ac21159e27f4	48	*
darran	0:ac21159e27f4	49	* This file is part of the lwIP TCP/IP stack.
darran	0:ac21159e27f4	50	*
darran	0:ac21159e27f4	51	* Author: Adam Dunkels <adam@sics.se>
darran	0:ac21159e27f4	52	* Simon Goldschmidt
darran	0:ac21159e27f4	53	*
darran	0:ac21159e27f4	54	*/
darran	0:ac21159e27f4	55
darran	0:ac21159e27f4	56	#include "lwip/opt.h"
darran	0:ac21159e27f4	57
darran	0:ac21159e27f4	58	#if !MEM_LIBC_MALLOC /* don't build if not configured for use in lwipopts.h */
darran	0:ac21159e27f4	59
darran	0:ac21159e27f4	60	#include "lwip/def.h"
darran	0:ac21159e27f4	61	#include "lwip/mem.h"
darran	0:ac21159e27f4	62	#include "lwip/sys.h"
darran	0:ac21159e27f4	63	#include "lwip/stats.h"
darran	0:ac21159e27f4	64	#include "lwip/err.h"
darran	0:ac21159e27f4	65
darran	0:ac21159e27f4	66	#include <string.h>
darran	0:ac21159e27f4	67
darran	0:ac21159e27f4	68	#if MEM_USE_POOLS
darran	0:ac21159e27f4	69	/* lwIP head implemented with different sized pools */
darran	0:ac21159e27f4	70
darran	0:ac21159e27f4	71	/**
darran	0:ac21159e27f4	72	* Allocate memory: determine the smallest pool that is big enough
darran	0:ac21159e27f4	73	* to contain an element of 'size' and get an element from that pool.
darran	0:ac21159e27f4	74	*
darran	0:ac21159e27f4	75	* @param size the size in bytes of the memory needed
darran	0:ac21159e27f4	76	* @return a pointer to the allocated memory or NULL if the pool is empty
darran	0:ac21159e27f4	77	*/
darran	0:ac21159e27f4	78	void *
darran	0:ac21159e27f4	79	mem_malloc(mem_size_t size)
darran	0:ac21159e27f4	80	{
darran	0:ac21159e27f4	81	struct memp_malloc_helper *element;
darran	0:ac21159e27f4	82	memp_t poolnr;
darran	0:ac21159e27f4	83	mem_size_t required_size = size + sizeof(struct memp_malloc_helper);
darran	0:ac21159e27f4	84
darran	0:ac21159e27f4	85	for (poolnr = MEMP_POOL_FIRST; poolnr <= MEMP_POOL_LAST; poolnr++) {
darran	0:ac21159e27f4	86	#if MEM_USE_POOLS_TRY_BIGGER_POOL
darran	0:ac21159e27f4	87	again:
darran	0:ac21159e27f4	88	#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
darran	0:ac21159e27f4	89	/* is this pool big enough to hold an element of the required size
darran	0:ac21159e27f4	90	plus a struct memp_malloc_helper that saves the pool this element came from? */
darran	0:ac21159e27f4	91	if (required_size <= memp_sizes[poolnr]) {
darran	0:ac21159e27f4	92	break;
darran	0:ac21159e27f4	93	}
darran	0:ac21159e27f4	94	}
darran	0:ac21159e27f4	95	if (poolnr > MEMP_POOL_LAST) {
darran	0:ac21159e27f4	96	LWIP_ASSERT("mem_malloc(): no pool is that big!", 0);
darran	0:ac21159e27f4	97	return NULL;
darran	0:ac21159e27f4	98	}
darran	0:ac21159e27f4	99	element = (struct memp_malloc_helper*)memp_malloc(poolnr);
darran	0:ac21159e27f4	100	if (element == NULL) {
darran	0:ac21159e27f4	101	/* No need to DEBUGF or ASSERT: This error is already
darran	0:ac21159e27f4	102	taken care of in memp.c */
darran	0:ac21159e27f4	103	#if MEM_USE_POOLS_TRY_BIGGER_POOL
darran	0:ac21159e27f4	104	/** Try a bigger pool if this one is empty! */
darran	0:ac21159e27f4	105	if (poolnr < MEMP_POOL_LAST) {
darran	0:ac21159e27f4	106	poolnr++;
darran	0:ac21159e27f4	107	goto again;
darran	0:ac21159e27f4	108	}
darran	0:ac21159e27f4	109	#endif /* MEM_USE_POOLS_TRY_BIGGER_POOL */
darran	0:ac21159e27f4	110	return NULL;
darran	0:ac21159e27f4	111	}
darran	0:ac21159e27f4	112
darran	0:ac21159e27f4	113	/* save the pool number this element came from */
darran	0:ac21159e27f4	114	element->poolnr = poolnr;
darran	0:ac21159e27f4	115	/* and return a pointer to the memory directly after the struct memp_malloc_helper */
darran	0:ac21159e27f4	116	element++;
darran	0:ac21159e27f4	117
darran	0:ac21159e27f4	118	return element;
darran	0:ac21159e27f4	119	}
darran	0:ac21159e27f4	120
darran	0:ac21159e27f4	121	/**
darran	0:ac21159e27f4	122	* Free memory previously allocated by mem_malloc. Loads the pool number
darran	0:ac21159e27f4	123	* and calls memp_free with that pool number to put the element back into
darran	0:ac21159e27f4	124	* its pool
darran	0:ac21159e27f4	125	*
darran	0:ac21159e27f4	126	* @param rmem the memory element to free
darran	0:ac21159e27f4	127	*/
darran	0:ac21159e27f4	128	void
darran	0:ac21159e27f4	129	mem_free(void *rmem)
darran	0:ac21159e27f4	130	{
darran	0:ac21159e27f4	131	struct memp_malloc_helper hmem = (struct memp_malloc_helper)rmem;
darran	0:ac21159e27f4	132
darran	0:ac21159e27f4	133	LWIP_ASSERT("rmem != NULL", (rmem != NULL));
darran	0:ac21159e27f4	134	LWIP_ASSERT("rmem == MEM_ALIGN(rmem)", (rmem == LWIP_MEM_ALIGN(rmem)));
darran	0:ac21159e27f4	135
darran	0:ac21159e27f4	136	/* get the original struct memp_malloc_helper */
darran	0:ac21159e27f4	137	hmem--;
darran	0:ac21159e27f4	138
darran	0:ac21159e27f4	139	LWIP_ASSERT("hmem != NULL", (hmem != NULL));
darran	0:ac21159e27f4	140	LWIP_ASSERT("hmem == MEM_ALIGN(hmem)", (hmem == LWIP_MEM_ALIGN(hmem)));
darran	0:ac21159e27f4	141	LWIP_ASSERT("hmem->poolnr < MEMP_MAX", (hmem->poolnr < MEMP_MAX));
darran	0:ac21159e27f4	142
darran	0:ac21159e27f4	143	/* and put it in the pool we saved earlier */
darran	0:ac21159e27f4	144	memp_free(hmem->poolnr, hmem);
darran	0:ac21159e27f4	145	}
darran	0:ac21159e27f4	146
darran	0:ac21159e27f4	147	#else /* MEM_USE_POOLS */
darran	0:ac21159e27f4	148	/* lwIP replacement for your libc malloc() */
darran	0:ac21159e27f4	149
darran	0:ac21159e27f4	150	/**
darran	0:ac21159e27f4	151	* The heap is made up as a list of structs of this type.
darran	0:ac21159e27f4	152	* This does not have to be aligned since for getting its size,
darran	0:ac21159e27f4	153	* we only use the macro SIZEOF_STRUCT_MEM, which automatically alignes.
darran	0:ac21159e27f4	154	*/
darran	0:ac21159e27f4	155	struct mem {
darran	0:ac21159e27f4	156	/** index (-> ram[next]) of the next struct */
darran	0:ac21159e27f4	157	mem_size_t next;
darran	0:ac21159e27f4	158	/** index (-> ram[prev]) of the previous struct */
darran	0:ac21159e27f4	159	mem_size_t prev;
darran	0:ac21159e27f4	160	/** 1: this area is used; 0: this area is unused */
darran	0:ac21159e27f4	161	u8_t used;
darran	0:ac21159e27f4	162	};
darran	0:ac21159e27f4	163
darran	0:ac21159e27f4	164	/** All allocated blocks will be MIN_SIZE bytes big, at least!
darran	0:ac21159e27f4	165	* MIN_SIZE can be overridden to suit your needs. Smaller values save space,
darran	0:ac21159e27f4	166	* larger values could prevent too small blocks to fragment the RAM too much. */
darran	0:ac21159e27f4	167	#ifndef MIN_SIZE
darran	0:ac21159e27f4	168	#define MIN_SIZE 12
darran	0:ac21159e27f4	169	#endif /* MIN_SIZE */
darran	0:ac21159e27f4	170	/* some alignment macros: we define them here for better source code layout */
darran	0:ac21159e27f4	171	#define MIN_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MIN_SIZE)
darran	0:ac21159e27f4	172	#define SIZEOF_STRUCT_MEM LWIP_MEM_ALIGN_SIZE(sizeof(struct mem))
darran	0:ac21159e27f4	173	#define MEM_SIZE_ALIGNED LWIP_MEM_ALIGN_SIZE(MEM_SIZE)
darran	0:ac21159e27f4	174
darran	0:ac21159e27f4	175	/** If you want to relocate the heap to external memory, simply define
darran	0:ac21159e27f4	176	* LWIP_RAM_HEAP_POINTER as a void-pointer to that location.
darran	0:ac21159e27f4	177	* If so, make sure the memory at that location is big enough (see below on
darran	0:ac21159e27f4	178	* how that space is calculated). */
darran	0:ac21159e27f4	179	#ifndef LWIP_RAM_HEAP_POINTER
darran	0:ac21159e27f4	180	/** the heap. we need one struct mem at the end and some room for alignment */
darran	0:ac21159e27f4	181	u8_t ram_heap[MEM_SIZE_ALIGNED + (2*SIZEOF_STRUCT_MEM) + MEM_ALIGNMENT] MEM_POSITION;
darran	0:ac21159e27f4	182	#define LWIP_RAM_HEAP_POINTER ram_heap
darran	0:ac21159e27f4	183	#endif /* LWIP_RAM_HEAP_POINTER */
darran	0:ac21159e27f4	184
darran	0:ac21159e27f4	185	/** pointer to the heap (ram_heap): for alignment, ram is now a pointer instead of an array */
darran	0:ac21159e27f4	186	static u8_t *ram;
darran	0:ac21159e27f4	187	/** the last entry, always unused! */
darran	0:ac21159e27f4	188	static struct mem *ram_end;
darran	0:ac21159e27f4	189	/** pointer to the lowest free block, this is used for faster search */
darran	0:ac21159e27f4	190	static struct mem *lfree;
darran	0:ac21159e27f4	191
darran	0:ac21159e27f4	192	#if (NO_SYS==0) //Pointless if monothreaded app
darran	0:ac21159e27f4	193	/** concurrent access protection */
darran	0:ac21159e27f4	194	static sys_mutex_t mem_mutex;
darran	0:ac21159e27f4	195	#endif
darran	0:ac21159e27f4	196
darran	0:ac21159e27f4	197	#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
darran	0:ac21159e27f4	198
darran	0:ac21159e27f4	199	static volatile u8_t mem_free_count;
darran	0:ac21159e27f4	200
darran	0:ac21159e27f4	201	/* Allow mem_free from other (e.g. interrupt) context */
darran	0:ac21159e27f4	202	#define LWIP_MEM_FREE_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_free)
darran	0:ac21159e27f4	203	#define LWIP_MEM_FREE_PROTECT() SYS_ARCH_PROTECT(lev_free)
darran	0:ac21159e27f4	204	#define LWIP_MEM_FREE_UNPROTECT() SYS_ARCH_UNPROTECT(lev_free)
darran	0:ac21159e27f4	205	#define LWIP_MEM_ALLOC_DECL_PROTECT() SYS_ARCH_DECL_PROTECT(lev_alloc)
darran	0:ac21159e27f4	206	#define LWIP_MEM_ALLOC_PROTECT() SYS_ARCH_PROTECT(lev_alloc)
darran	0:ac21159e27f4	207	#define LWIP_MEM_ALLOC_UNPROTECT() SYS_ARCH_UNPROTECT(lev_alloc)
darran	0:ac21159e27f4	208
darran	0:ac21159e27f4	209	#else /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	210
darran	0:ac21159e27f4	211	/* Protect the heap only by using a semaphore */
darran	0:ac21159e27f4	212	#define LWIP_MEM_FREE_DECL_PROTECT()
darran	0:ac21159e27f4	213	#define LWIP_MEM_FREE_PROTECT() sys_mutex_lock(&mem_mutex)
darran	0:ac21159e27f4	214	#define LWIP_MEM_FREE_UNPROTECT() sys_mutex_unlock(&mem_mutex)
darran	0:ac21159e27f4	215	/* mem_malloc is protected using semaphore AND LWIP_MEM_ALLOC_PROTECT */
darran	0:ac21159e27f4	216	#define LWIP_MEM_ALLOC_DECL_PROTECT()
darran	0:ac21159e27f4	217	#define LWIP_MEM_ALLOC_PROTECT()
darran	0:ac21159e27f4	218	#define LWIP_MEM_ALLOC_UNPROTECT()
darran	0:ac21159e27f4	219
darran	0:ac21159e27f4	220	#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	221
darran	0:ac21159e27f4	222
darran	0:ac21159e27f4	223	/**
darran	0:ac21159e27f4	224	* "Plug holes" by combining adjacent empty struct mems.
darran	0:ac21159e27f4	225	* After this function is through, there should not exist
darran	0:ac21159e27f4	226	* one empty struct mem pointing to another empty struct mem.
darran	0:ac21159e27f4	227	*
darran	0:ac21159e27f4	228	* @param mem this points to a struct mem which just has been freed
darran	0:ac21159e27f4	229	* @internal this function is only called by mem_free() and mem_trim()
darran	0:ac21159e27f4	230	*
darran	0:ac21159e27f4	231	* This assumes access to the heap is protected by the calling function
darran	0:ac21159e27f4	232	* already.
darran	0:ac21159e27f4	233	*/
darran	0:ac21159e27f4	234	static void
darran	0:ac21159e27f4	235	plug_holes(struct mem *mem)
darran	0:ac21159e27f4	236	{
darran	0:ac21159e27f4	237	struct mem *nmem;
darran	0:ac21159e27f4	238	struct mem *pmem;
darran	0:ac21159e27f4	239
darran	0:ac21159e27f4	240	LWIP_ASSERT("plug_holes: mem >= ram", (u8_t *)mem >= ram);
darran	0:ac21159e27f4	241	LWIP_ASSERT("plug_holes: mem < ram_end", (u8_t )mem < (u8_t )ram_end);
darran	0:ac21159e27f4	242	LWIP_ASSERT("plug_holes: mem->used == 0", mem->used == 0);
darran	0:ac21159e27f4	243
darran	0:ac21159e27f4	244	/* plug hole forward */
darran	0:ac21159e27f4	245	LWIP_ASSERT("plug_holes: mem->next <= MEM_SIZE_ALIGNED", mem->next <= MEM_SIZE_ALIGNED);
darran	0:ac21159e27f4	246
darran	0:ac21159e27f4	247	nmem = (struct mem )(void )&ram[mem->next];
darran	0:ac21159e27f4	248	if (mem != nmem && nmem->used == 0 && (u8_t )nmem != (u8_t )ram_end) {
darran	0:ac21159e27f4	249	/* if mem->next is unused and not end of ram, combine mem and mem->next */
darran	0:ac21159e27f4	250	if (lfree == nmem) {
darran	0:ac21159e27f4	251	lfree = mem;
darran	0:ac21159e27f4	252	}
darran	0:ac21159e27f4	253	mem->next = nmem->next;
darran	0:ac21159e27f4	254	((struct mem )(void )&ram[nmem->next])->prev = (mem_size_t)((u8_t *)mem - ram);
darran	0:ac21159e27f4	255	}
darran	0:ac21159e27f4	256
darran	0:ac21159e27f4	257	/* plug hole backward */
darran	0:ac21159e27f4	258	pmem = (struct mem )(void )&ram[mem->prev];
darran	0:ac21159e27f4	259	if (pmem != mem && pmem->used == 0) {
darran	0:ac21159e27f4	260	/* if mem->prev is unused, combine mem and mem->prev */
darran	0:ac21159e27f4	261	if (lfree == mem) {
darran	0:ac21159e27f4	262	lfree = pmem;
darran	0:ac21159e27f4	263	}
darran	0:ac21159e27f4	264	pmem->next = mem->next;
darran	0:ac21159e27f4	265	((struct mem )(void )&ram[mem->next])->prev = (mem_size_t)((u8_t *)pmem - ram);
darran	0:ac21159e27f4	266	}
darran	0:ac21159e27f4	267	}
darran	0:ac21159e27f4	268
darran	0:ac21159e27f4	269	/**
darran	0:ac21159e27f4	270	* Zero the heap and initialize start, end and lowest-free
darran	0:ac21159e27f4	271	*/
darran	0:ac21159e27f4	272	void
darran	0:ac21159e27f4	273	mem_init(void)
darran	0:ac21159e27f4	274	{
darran	0:ac21159e27f4	275	struct mem *mem;
darran	0:ac21159e27f4	276
darran	0:ac21159e27f4	277	LWIP_ASSERT("Sanity check alignment",
darran	0:ac21159e27f4	278	(SIZEOF_STRUCT_MEM & (MEM_ALIGNMENT-1)) == 0);
darran	0:ac21159e27f4	279
darran	0:ac21159e27f4	280	/* align the heap */
darran	0:ac21159e27f4	281	ram = (u8_t *)LWIP_MEM_ALIGN(LWIP_RAM_HEAP_POINTER);
darran	0:ac21159e27f4	282	/* initialize the start of the heap */
darran	0:ac21159e27f4	283	mem = (struct mem )(void )ram;
darran	0:ac21159e27f4	284	mem->next = MEM_SIZE_ALIGNED;
darran	0:ac21159e27f4	285	mem->prev = 0;
darran	0:ac21159e27f4	286	mem->used = 0;
darran	0:ac21159e27f4	287	/* initialize the end of the heap */
darran	0:ac21159e27f4	288	ram_end = (struct mem )(void )&ram[MEM_SIZE_ALIGNED];
darran	0:ac21159e27f4	289	ram_end->used = 1;
darran	0:ac21159e27f4	290	ram_end->next = MEM_SIZE_ALIGNED;
darran	0:ac21159e27f4	291	ram_end->prev = MEM_SIZE_ALIGNED;
darran	0:ac21159e27f4	292
darran	0:ac21159e27f4	293	/* initialize the lowest-free pointer to the start of the heap */
darran	0:ac21159e27f4	294	lfree = (struct mem )(void )ram;
darran	0:ac21159e27f4	295
darran	0:ac21159e27f4	296	MEM_STATS_AVAIL(avail, MEM_SIZE_ALIGNED);
darran	0:ac21159e27f4	297
darran	0:ac21159e27f4	298	if(sys_mutex_new(&mem_mutex) != ERR_OK) {
darran	0:ac21159e27f4	299	LWIP_ASSERT("failed to create mem_mutex", 0);
darran	0:ac21159e27f4	300	}
darran	0:ac21159e27f4	301	}
darran	0:ac21159e27f4	302
darran	0:ac21159e27f4	303	/**
darran	0:ac21159e27f4	304	* Put a struct mem back on the heap
darran	0:ac21159e27f4	305	*
darran	0:ac21159e27f4	306	* @param rmem is the data portion of a struct mem as returned by a previous
darran	0:ac21159e27f4	307	* call to mem_malloc()
darran	0:ac21159e27f4	308	*/
darran	0:ac21159e27f4	309	void
darran	0:ac21159e27f4	310	mem_free(void *rmem)
darran	0:ac21159e27f4	311	{
darran	0:ac21159e27f4	312	struct mem *mem;
darran	0:ac21159e27f4	313	LWIP_MEM_FREE_DECL_PROTECT();
darran	0:ac21159e27f4	314
darran	0:ac21159e27f4	315	if (rmem == NULL) {
darran	0:ac21159e27f4	316	LWIP_DEBUGF(MEM_DEBUG \| LWIP_DBG_TRACE \| LWIP_DBG_LEVEL_SERIOUS, ("mem_free(p == NULL) was called.\n"));
darran	0:ac21159e27f4	317	return;
darran	0:ac21159e27f4	318	}
darran	0:ac21159e27f4	319	LWIP_ASSERT("mem_free: sanity check alignment", (((mem_ptr_t)rmem) & (MEM_ALIGNMENT-1)) == 0);
darran	0:ac21159e27f4	320
darran	0:ac21159e27f4	321	LWIP_ASSERT("mem_free: legal memory", (u8_t )rmem >= (u8_t )ram &&
darran	0:ac21159e27f4	322	(u8_t )rmem < (u8_t )ram_end);
darran	0:ac21159e27f4	323
darran	0:ac21159e27f4	324	if ((u8_t )rmem < (u8_t )ram \|\| (u8_t )rmem >= (u8_t )ram_end) {
darran	0:ac21159e27f4	325	SYS_ARCH_DECL_PROTECT(lev);
darran	0:ac21159e27f4	326	LWIP_DEBUGF(MEM_DEBUG \| LWIP_DBG_LEVEL_SEVERE, ("mem_free: illegal memory\n"));
darran	0:ac21159e27f4	327	/* protect mem stats from concurrent access */
darran	0:ac21159e27f4	328	SYS_ARCH_PROTECT(lev);
darran	0:ac21159e27f4	329	MEM_STATS_INC(illegal);
darran	0:ac21159e27f4	330	SYS_ARCH_UNPROTECT(lev);
darran	0:ac21159e27f4	331	return;
darran	0:ac21159e27f4	332	}
darran	0:ac21159e27f4	333	/* protect the heap from concurrent access */
darran	0:ac21159e27f4	334	LWIP_MEM_FREE_PROTECT();
darran	0:ac21159e27f4	335	/* Get the corresponding struct mem ... */
darran	0:ac21159e27f4	336	mem = (struct mem )(void )((u8_t *)rmem - SIZEOF_STRUCT_MEM);
darran	0:ac21159e27f4	337	/* ... which has to be in a used state ... */
darran	0:ac21159e27f4	338	LWIP_ASSERT("mem_free: mem->used", mem->used);
darran	0:ac21159e27f4	339	/* ... and is now unused. */
darran	0:ac21159e27f4	340	mem->used = 0;
darran	0:ac21159e27f4	341
darran	0:ac21159e27f4	342	if (mem < lfree) {
darran	0:ac21159e27f4	343	/* the newly freed struct is now the lowest */
darran	0:ac21159e27f4	344	lfree = mem;
darran	0:ac21159e27f4	345	}
darran	0:ac21159e27f4	346
darran	0:ac21159e27f4	347	MEM_STATS_DEC_USED(used, mem->next - (mem_size_t)(((u8_t *)mem - ram)));
darran	0:ac21159e27f4	348
darran	0:ac21159e27f4	349	/* finally, see if prev or next are free also */
darran	0:ac21159e27f4	350	plug_holes(mem);
darran	0:ac21159e27f4	351	#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
darran	0:ac21159e27f4	352	mem_free_count = 1;
darran	0:ac21159e27f4	353	#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	354	LWIP_MEM_FREE_UNPROTECT();
darran	0:ac21159e27f4	355	}
darran	0:ac21159e27f4	356
darran	0:ac21159e27f4	357	/**
darran	0:ac21159e27f4	358	* Shrink memory returned by mem_malloc().
darran	0:ac21159e27f4	359	*
darran	0:ac21159e27f4	360	* @param rmem pointer to memory allocated by mem_malloc the is to be shrinked
darran	0:ac21159e27f4	361	* @param newsize required size after shrinking (needs to be smaller than or
darran	0:ac21159e27f4	362	* equal to the previous size)
darran	0:ac21159e27f4	363	* @return for compatibility reasons: is always == rmem, at the moment
darran	0:ac21159e27f4	364	* or NULL if newsize is > old size, in which case rmem is NOT touched
darran	0:ac21159e27f4	365	* or freed!
darran	0:ac21159e27f4	366	*/
darran	0:ac21159e27f4	367	void *
darran	0:ac21159e27f4	368	mem_trim(void *rmem, mem_size_t newsize)
darran	0:ac21159e27f4	369	{
darran	0:ac21159e27f4	370	mem_size_t size;
darran	0:ac21159e27f4	371	mem_size_t ptr, ptr2;
darran	0:ac21159e27f4	372	struct mem mem, mem2;
darran	0:ac21159e27f4	373	/* use the FREE_PROTECT here: it protects with sem OR SYS_ARCH_PROTECT */
darran	0:ac21159e27f4	374	LWIP_MEM_FREE_DECL_PROTECT();
darran	0:ac21159e27f4	375
darran	0:ac21159e27f4	376	/* Expand the size of the allocated memory region so that we can
darran	0:ac21159e27f4	377	adjust for alignment. */
darran	0:ac21159e27f4	378	newsize = LWIP_MEM_ALIGN_SIZE(newsize);
darran	0:ac21159e27f4	379
darran	0:ac21159e27f4	380	if(newsize < MIN_SIZE_ALIGNED) {
darran	0:ac21159e27f4	381	/* every data block must be at least MIN_SIZE_ALIGNED long */
darran	0:ac21159e27f4	382	newsize = MIN_SIZE_ALIGNED;
darran	0:ac21159e27f4	383	}
darran	0:ac21159e27f4	384
darran	0:ac21159e27f4	385	if (newsize > MEM_SIZE_ALIGNED) {
darran	0:ac21159e27f4	386	return NULL;
darran	0:ac21159e27f4	387	}
darran	0:ac21159e27f4	388
darran	0:ac21159e27f4	389	LWIP_ASSERT("mem_trim: legal memory", (u8_t )rmem >= (u8_t )ram &&
darran	0:ac21159e27f4	390	(u8_t )rmem < (u8_t )ram_end);
darran	0:ac21159e27f4	391
darran	0:ac21159e27f4	392	if ((u8_t )rmem < (u8_t )ram \|\| (u8_t )rmem >= (u8_t )ram_end) {
darran	0:ac21159e27f4	393	SYS_ARCH_DECL_PROTECT(lev);
darran	0:ac21159e27f4	394	LWIP_DEBUGF(MEM_DEBUG \| LWIP_DBG_LEVEL_SEVERE, ("mem_trim: illegal memory\n"));
darran	0:ac21159e27f4	395	/* protect mem stats from concurrent access */
darran	0:ac21159e27f4	396	SYS_ARCH_PROTECT(lev);
darran	0:ac21159e27f4	397	MEM_STATS_INC(illegal);
darran	0:ac21159e27f4	398	SYS_ARCH_UNPROTECT(lev);
darran	0:ac21159e27f4	399	return rmem;
darran	0:ac21159e27f4	400	}
darran	0:ac21159e27f4	401	/* Get the corresponding struct mem ... */
darran	0:ac21159e27f4	402	mem = (struct mem )(void )((u8_t *)rmem - SIZEOF_STRUCT_MEM);
darran	0:ac21159e27f4	403	/* ... and its offset pointer */
darran	0:ac21159e27f4	404	ptr = (mem_size_t)((u8_t *)mem - ram);
darran	0:ac21159e27f4	405
darran	0:ac21159e27f4	406	size = mem->next - ptr - SIZEOF_STRUCT_MEM;
darran	0:ac21159e27f4	407	LWIP_ASSERT("mem_trim can only shrink memory", newsize <= size);
darran	0:ac21159e27f4	408	if (newsize > size) {
darran	0:ac21159e27f4	409	/* not supported */
darran	0:ac21159e27f4	410	return NULL;
darran	0:ac21159e27f4	411	}
darran	0:ac21159e27f4	412	if (newsize == size) {
darran	0:ac21159e27f4	413	/* No change in size, simply return */
darran	0:ac21159e27f4	414	return rmem;
darran	0:ac21159e27f4	415	}
darran	0:ac21159e27f4	416
darran	0:ac21159e27f4	417	/* protect the heap from concurrent access */
darran	0:ac21159e27f4	418	LWIP_MEM_FREE_PROTECT();
darran	0:ac21159e27f4	419
darran	0:ac21159e27f4	420	mem2 = (struct mem )(void )&ram[mem->next];
darran	0:ac21159e27f4	421	if(mem2->used == 0) {
darran	0:ac21159e27f4	422	/* The next struct is unused, we can simply move it at little */
darran	0:ac21159e27f4	423	mem_size_t next;
darran	0:ac21159e27f4	424	/* remember the old next pointer */
darran	0:ac21159e27f4	425	next = mem2->next;
darran	0:ac21159e27f4	426	/* create new struct mem which is moved directly after the shrinked mem */
darran	0:ac21159e27f4	427	ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
darran	0:ac21159e27f4	428	if (lfree == mem2) {
darran	0:ac21159e27f4	429	lfree = (struct mem )(void )&ram[ptr2];
darran	0:ac21159e27f4	430	}
darran	0:ac21159e27f4	431	mem2 = (struct mem )(void )&ram[ptr2];
darran	0:ac21159e27f4	432	mem2->used = 0;
darran	0:ac21159e27f4	433	/* restore the next pointer */
darran	0:ac21159e27f4	434	mem2->next = next;
darran	0:ac21159e27f4	435	/* link it back to mem */
darran	0:ac21159e27f4	436	mem2->prev = ptr;
darran	0:ac21159e27f4	437	/* link mem to it */
darran	0:ac21159e27f4	438	mem->next = ptr2;
darran	0:ac21159e27f4	439	/* last thing to restore linked list: as we have moved mem2,
darran	0:ac21159e27f4	440	* let 'mem2->next->prev' point to mem2 again. but only if mem2->next is not
darran	0:ac21159e27f4	441	* the end of the heap */
darran	0:ac21159e27f4	442	if (mem2->next != MEM_SIZE_ALIGNED) {
darran	0:ac21159e27f4	443	((struct mem )(void )&ram[mem2->next])->prev = ptr2;
darran	0:ac21159e27f4	444	}
darran	0:ac21159e27f4	445	MEM_STATS_DEC_USED(used, (size - newsize));
darran	0:ac21159e27f4	446	/* no need to plug holes, we've already done that */
darran	0:ac21159e27f4	447	} else if (newsize + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED <= size) {
darran	0:ac21159e27f4	448	/* Next struct is used but there's room for another struct mem with
darran	0:ac21159e27f4	449	* at least MIN_SIZE_ALIGNED of data.
darran	0:ac21159e27f4	450	* Old size ('size') must be big enough to contain at least 'newsize' plus a struct mem
darran	0:ac21159e27f4	451	* ('SIZEOF_STRUCT_MEM') with some data ('MIN_SIZE_ALIGNED').
darran	0:ac21159e27f4	452	* @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
darran	0:ac21159e27f4	453	* region that couldn't hold data, but when mem->next gets freed,
darran	0:ac21159e27f4	454	* the 2 regions would be combined, resulting in more free memory */
darran	0:ac21159e27f4	455	ptr2 = ptr + SIZEOF_STRUCT_MEM + newsize;
darran	0:ac21159e27f4	456	mem2 = (struct mem )(void )&ram[ptr2];
darran	0:ac21159e27f4	457	if (mem2 < lfree) {
darran	0:ac21159e27f4	458	lfree = mem2;
darran	0:ac21159e27f4	459	}
darran	0:ac21159e27f4	460	mem2->used = 0;
darran	0:ac21159e27f4	461	mem2->next = mem->next;
darran	0:ac21159e27f4	462	mem2->prev = ptr;
darran	0:ac21159e27f4	463	mem->next = ptr2;
darran	0:ac21159e27f4	464	if (mem2->next != MEM_SIZE_ALIGNED) {
darran	0:ac21159e27f4	465	((struct mem )(void )&ram[mem2->next])->prev = ptr2;
darran	0:ac21159e27f4	466	}
darran	0:ac21159e27f4	467	MEM_STATS_DEC_USED(used, (size - newsize));
darran	0:ac21159e27f4	468	/* the original mem->next is used, so no need to plug holes! */
darran	0:ac21159e27f4	469	}
darran	0:ac21159e27f4	470	/* else {
darran	0:ac21159e27f4	471	next struct mem is used but size between mem and mem2 is not big enough
darran	0:ac21159e27f4	472	to create another struct mem
darran	0:ac21159e27f4	473	-> don't do anyhting.
darran	0:ac21159e27f4	474	-> the remaining space stays unused since it is too small
darran	0:ac21159e27f4	475	} */
darran	0:ac21159e27f4	476	#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
darran	0:ac21159e27f4	477	mem_free_count = 1;
darran	0:ac21159e27f4	478	#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	479	LWIP_MEM_FREE_UNPROTECT();
darran	0:ac21159e27f4	480	return rmem;
darran	0:ac21159e27f4	481	}
darran	0:ac21159e27f4	482
darran	0:ac21159e27f4	483	/**
darran	0:ac21159e27f4	484	* Adam's mem_malloc() plus solution for bug #17922
darran	0:ac21159e27f4	485	* Allocate a block of memory with a minimum of 'size' bytes.
darran	0:ac21159e27f4	486	*
darran	0:ac21159e27f4	487	* @param size is the minimum size of the requested block in bytes.
darran	0:ac21159e27f4	488	* @return pointer to allocated memory or NULL if no free memory was found.
darran	0:ac21159e27f4	489	*
darran	0:ac21159e27f4	490	* Note that the returned value will always be aligned (as defined by MEM_ALIGNMENT).
darran	0:ac21159e27f4	491	*/
darran	0:ac21159e27f4	492	void *
darran	0:ac21159e27f4	493	mem_malloc(mem_size_t size)
darran	0:ac21159e27f4	494	{
darran	0:ac21159e27f4	495	mem_size_t ptr, ptr2;
darran	0:ac21159e27f4	496	struct mem mem, mem2;
darran	0:ac21159e27f4	497	#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
darran	0:ac21159e27f4	498	u8_t local_mem_free_count = 0;
darran	0:ac21159e27f4	499	#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	500	LWIP_MEM_ALLOC_DECL_PROTECT();
darran	0:ac21159e27f4	501
darran	0:ac21159e27f4	502	if (size == 0) {
darran	0:ac21159e27f4	503	return NULL;
darran	0:ac21159e27f4	504	}
darran	0:ac21159e27f4	505
darran	0:ac21159e27f4	506	/* Expand the size of the allocated memory region so that we can
darran	0:ac21159e27f4	507	adjust for alignment. */
darran	0:ac21159e27f4	508	size = LWIP_MEM_ALIGN_SIZE(size);
darran	0:ac21159e27f4	509
darran	0:ac21159e27f4	510	if(size < MIN_SIZE_ALIGNED) {
darran	0:ac21159e27f4	511	/* every data block must be at least MIN_SIZE_ALIGNED long */
darran	0:ac21159e27f4	512	size = MIN_SIZE_ALIGNED;
darran	0:ac21159e27f4	513	}
darran	0:ac21159e27f4	514
darran	0:ac21159e27f4	515	if (size > MEM_SIZE_ALIGNED) {
darran	0:ac21159e27f4	516	return NULL;
darran	0:ac21159e27f4	517	}
darran	0:ac21159e27f4	518
darran	0:ac21159e27f4	519	/* protect the heap from concurrent access */
darran	0:ac21159e27f4	520	sys_mutex_lock(&mem_mutex);
darran	0:ac21159e27f4	521	LWIP_MEM_ALLOC_PROTECT();
darran	0:ac21159e27f4	522	#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
darran	0:ac21159e27f4	523	/* run as long as a mem_free disturbed mem_malloc */
darran	0:ac21159e27f4	524	do {
darran	0:ac21159e27f4	525	local_mem_free_count = 0;
darran	0:ac21159e27f4	526	#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	527
darran	0:ac21159e27f4	528	/* Scan through the heap searching for a free block that is big enough,
darran	0:ac21159e27f4	529	* beginning with the lowest free block.
darran	0:ac21159e27f4	530	*/
darran	0:ac21159e27f4	531	for (ptr = (mem_size_t)((u8_t *)lfree - ram); ptr < MEM_SIZE_ALIGNED - size;
darran	0:ac21159e27f4	532	ptr = ((struct mem )(void )&ram[ptr])->next) {
darran	0:ac21159e27f4	533	mem = (struct mem )(void )&ram[ptr];
darran	0:ac21159e27f4	534	#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
darran	0:ac21159e27f4	535	mem_free_count = 0;
darran	0:ac21159e27f4	536	LWIP_MEM_ALLOC_UNPROTECT();
darran	0:ac21159e27f4	537	/* allow mem_free to run */
darran	0:ac21159e27f4	538	LWIP_MEM_ALLOC_PROTECT();
darran	0:ac21159e27f4	539	if (mem_free_count != 0) {
darran	0:ac21159e27f4	540	local_mem_free_count = mem_free_count;
darran	0:ac21159e27f4	541	}
darran	0:ac21159e27f4	542	mem_free_count = 0;
darran	0:ac21159e27f4	543	#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	544
darran	0:ac21159e27f4	545	if ((!mem->used) &&
darran	0:ac21159e27f4	546	(mem->next - (ptr + SIZEOF_STRUCT_MEM)) >= size) {
darran	0:ac21159e27f4	547	/* mem is not used and at least perfect fit is possible:
darran	0:ac21159e27f4	548	* mem->next - (ptr + SIZEOF_STRUCT_MEM) gives us the 'user data size' of mem */
darran	0:ac21159e27f4	549
darran	0:ac21159e27f4	550	if (mem->next - (ptr + SIZEOF_STRUCT_MEM) >= (size + SIZEOF_STRUCT_MEM + MIN_SIZE_ALIGNED)) {
darran	0:ac21159e27f4	551	/* (in addition to the above, we test if another struct mem (SIZEOF_STRUCT_MEM) containing
darran	0:ac21159e27f4	552	* at least MIN_SIZE_ALIGNED of data also fits in the 'user data space' of 'mem')
darran	0:ac21159e27f4	553	* -> split large block, create empty remainder,
darran	0:ac21159e27f4	554	* remainder must be large enough to contain MIN_SIZE_ALIGNED data: if
darran	0:ac21159e27f4	555	* mem->next - (ptr + (2*SIZEOF_STRUCT_MEM)) == size,
darran	0:ac21159e27f4	556	* struct mem would fit in but no data between mem2 and mem2->next
darran	0:ac21159e27f4	557	* @todo we could leave out MIN_SIZE_ALIGNED. We would create an empty
darran	0:ac21159e27f4	558	* region that couldn't hold data, but when mem->next gets freed,
darran	0:ac21159e27f4	559	* the 2 regions would be combined, resulting in more free memory
darran	0:ac21159e27f4	560	*/
darran	0:ac21159e27f4	561	ptr2 = ptr + SIZEOF_STRUCT_MEM + size;
darran	0:ac21159e27f4	562	/* create mem2 struct */
darran	0:ac21159e27f4	563	mem2 = (struct mem )(void )&ram[ptr2];
darran	0:ac21159e27f4	564	mem2->used = 0;
darran	0:ac21159e27f4	565	mem2->next = mem->next;
darran	0:ac21159e27f4	566	mem2->prev = ptr;
darran	0:ac21159e27f4	567	/* and insert it between mem and mem->next */
darran	0:ac21159e27f4	568	mem->next = ptr2;
darran	0:ac21159e27f4	569	mem->used = 1;
darran	0:ac21159e27f4	570
darran	0:ac21159e27f4	571	if (mem2->next != MEM_SIZE_ALIGNED) {
darran	0:ac21159e27f4	572	((struct mem )(void )&ram[mem2->next])->prev = ptr2;
darran	0:ac21159e27f4	573	}
darran	0:ac21159e27f4	574	MEM_STATS_INC_USED(used, (size + SIZEOF_STRUCT_MEM));
darran	0:ac21159e27f4	575	} else {
darran	0:ac21159e27f4	576	/* (a mem2 struct does no fit into the user data space of mem and mem->next will always
darran	0:ac21159e27f4	577	* be used at this point: if not we have 2 unused structs in a row, plug_holes should have
darran	0:ac21159e27f4	578	* take care of this).
darran	0:ac21159e27f4	579	* -> near fit or excact fit: do not split, no mem2 creation
darran	0:ac21159e27f4	580	* also can't move mem->next directly behind mem, since mem->next
darran	0:ac21159e27f4	581	* will always be used at this point!
darran	0:ac21159e27f4	582	*/
darran	0:ac21159e27f4	583	mem->used = 1;
darran	0:ac21159e27f4	584	MEM_STATS_INC_USED(used, mem->next - (mem_size_t)((u8_t *)mem - ram));
darran	0:ac21159e27f4	585	}
darran	0:ac21159e27f4	586
darran	0:ac21159e27f4	587	if (mem == lfree) {
darran	0:ac21159e27f4	588	/* Find next free block after mem and update lowest free pointer */
darran	0:ac21159e27f4	589	while (lfree->used && lfree != ram_end) {
darran	0:ac21159e27f4	590	LWIP_MEM_ALLOC_UNPROTECT();
darran	0:ac21159e27f4	591	/* prevent high interrupt latency... */
darran	0:ac21159e27f4	592	LWIP_MEM_ALLOC_PROTECT();
darran	0:ac21159e27f4	593	lfree = (struct mem )(void )&ram[lfree->next];
darran	0:ac21159e27f4	594	}
darran	0:ac21159e27f4	595	LWIP_ASSERT("mem_malloc: !lfree->used", ((lfree == ram_end) \|\| (!lfree->used)));
darran	0:ac21159e27f4	596	}
darran	0:ac21159e27f4	597	LWIP_MEM_ALLOC_UNPROTECT();
darran	0:ac21159e27f4	598	sys_mutex_unlock(&mem_mutex);
darran	0:ac21159e27f4	599	LWIP_ASSERT("mem_malloc: allocated memory not above ram_end.",
darran	0:ac21159e27f4	600	(mem_ptr_t)mem + SIZEOF_STRUCT_MEM + size <= (mem_ptr_t)ram_end);
darran	0:ac21159e27f4	601	LWIP_ASSERT("mem_malloc: allocated memory properly aligned.",
darran	0:ac21159e27f4	602	((mem_ptr_t)mem + SIZEOF_STRUCT_MEM) % MEM_ALIGNMENT == 0);
darran	0:ac21159e27f4	603	LWIP_ASSERT("mem_malloc: sanity check alignment",
darran	0:ac21159e27f4	604	(((mem_ptr_t)mem) & (MEM_ALIGNMENT-1)) == 0);
darran	0:ac21159e27f4	605
darran	0:ac21159e27f4	606	return (u8_t *)mem + SIZEOF_STRUCT_MEM;
darran	0:ac21159e27f4	607	}
darran	0:ac21159e27f4	608	}
darran	0:ac21159e27f4	609	#if LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT
darran	0:ac21159e27f4	610	/* if we got interrupted by a mem_free, try again */
darran	0:ac21159e27f4	611	} while(local_mem_free_count != 0);
darran	0:ac21159e27f4	612	#endif /* LWIP_ALLOW_MEM_FREE_FROM_OTHER_CONTEXT */
darran	0:ac21159e27f4	613	LWIP_DEBUGF(MEM_DEBUG \| LWIP_DBG_LEVEL_SERIOUS, ("mem_malloc: could not allocate %"S16_F" bytes\n", (s16_t)size));
darran	0:ac21159e27f4	614	MEM_STATS_INC(err);
darran	0:ac21159e27f4	615	LWIP_MEM_ALLOC_UNPROTECT();
darran	0:ac21159e27f4	616	sys_mutex_unlock(&mem_mutex);
darran	0:ac21159e27f4	617	return NULL;
darran	0:ac21159e27f4	618	}
darran	0:ac21159e27f4	619
darran	0:ac21159e27f4	620	#endif /* MEM_USE_POOLS */
darran	0:ac21159e27f4	621	/**
darran	0:ac21159e27f4	622	* Contiguously allocates enough space for count objects that are size bytes
darran	0:ac21159e27f4	623	* of memory each and returns a pointer to the allocated memory.
darran	0:ac21159e27f4	624	*
darran	0:ac21159e27f4	625	* The allocated memory is filled with bytes of value zero.
darran	0:ac21159e27f4	626	*
darran	0:ac21159e27f4	627	* @param count number of objects to allocate
darran	0:ac21159e27f4	628	* @param size size of the objects to allocate
darran	0:ac21159e27f4	629	* @return pointer to allocated memory / NULL pointer if there is an error
darran	0:ac21159e27f4	630	*/
darran	0:ac21159e27f4	631	void *mem_calloc(mem_size_t count, mem_size_t size)
darran	0:ac21159e27f4	632	{
darran	0:ac21159e27f4	633	void *p;
darran	0:ac21159e27f4	634
darran	0:ac21159e27f4	635	/* allocate 'count' objects of size 'size' */
darran	0:ac21159e27f4	636	p = mem_malloc(count * size);
darran	0:ac21159e27f4	637	if (p) {
darran	0:ac21159e27f4	638	/* zero the memory */
darran	0:ac21159e27f4	639	memset(p, 0, count * size);
darran	0:ac21159e27f4	640	}
darran	0:ac21159e27f4	641	return p;
darran	0:ac21159e27f4	642	}
darran	0:ac21159e27f4	643
darran	0:ac21159e27f4	644	#endif /* !MEM_LIBC_MALLOC */

Repository toolbox

Export to desktop IDE

Build repository

Repository details

Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	02 Jul 2010
Imports:	2
Forks:	0
Commits:	1
Dependents:	0
Dependencies:	1
Followers:	1

lwip/core/mem.c@0:ac21159e27f4, 2010-07-02 (annotated)

Who changed what in which revision?

Repository toolbox

Repository details

Important Information for this Arm website

Access Warning